70803. There are 3 white balls and 2 black balls.If a ball is taken random,what is the probability that it is a black ball?
70804. Blast furnace is used to produce
70805. In flame hardening, oxy-acetylene flame is used.
70806. Which of the following statements are true for annealing of steels?
70807. The ability of a material to undergo large permanent deformation with the application of a tensile force, is called ductility.
70808. Which of the following steel making process is being adopted at Rourkela Steel Plant?
70809. 18-4-1 high speed steel contains
70810. Which of the following statement is true about brittle fracture?
70811. Grey cast iron has
70812. Induction hardening is basically a
70813. When elements like nickel, chromium, copper and molybdenum are added to the molten cast iron, it produces
70814. The strength is the ability of a material to resist
70815. The material widely used for making pendulums of clocks is
70816. The stiffness is the ability of a material to resist
70817. The blade of a power saw is made of
70818. In induction hardening __________ is high.
70819. The metal suitable for bearings subjected to light loads, is
70820. The property of a material essential for spring materials is
70821. A steel with carbon above 0.8% is known as hyper-eutectoid steel.
70822. Which of the following material has nearly zero coefficient of expansion?
70823. In normalising process, the hypo-eutectiod steel is heated from 30° C to 50° C above the upper critical temperature and then cooled in still air.
70824. The alloying element which can replace tungsten in high speed steels is
70825. An aluminium alloy with 11% silicon is used for making engine pistons by die casting technique.
70826. Which of the following is an amorphous material?
70827. The machinability of steel is improved by adding
70828. The carbon in the pig iron varies from
70829. The type of space lattice found in alpha-iron is
70830. The brown smoke during the operation of a bessemer Converter indicates that the
70831. Martensite has needle like structure and is magnetic.
70832. A and B start business in partnership by investing Rs.3,000 and Rs.4,000 respectively.At the end of one year a profit of Rs.1,400 is made.How much amount would A get as his share of profit?
70833. In induction hardening, the depth of hardening is controlled by controlling the voltage.
70834. The austenite is a solid solution of carbon or iron carbide in gamma-iron.
70835. Which of the following display properties similar to that of steel?
70836. Hindalium is an alloy of aluminium and magnesium with a small quantity of chromium.
70837. When a low carbon steel is heated upto upper critical temperature
70838. The steel widely used for motor car crankshafts is
70839. Combined carbon in iron makes the metal
70840. Pearlite consists of
70841. Incoloy, Hastelloy and Vitallium are __________ temperature alloys.
70842. Quenching is not necessary when hardening is done by
70843. The iron ore in the charge of blast furnace acts as an iron bearing mineral.
70844. Beryllium bronze has
70845. The aluminium alloy, mainly used, for anodized utensil manufacture, is
70846. The toughness of a material __________ when it is heated.
70847. The coordination number of a face centred cubic space lattice is
70848. Spheroidal grey cast iron has graphite flakes.
70849. Bronze is an alloy of
70850. Chromium when added to steel __________ the tensile strength.